The present invention relates to a method and device for vehicle battery protection, especially to a method and device for vehicle battery protection with battery power source noise pattern analysis that manages power consumption and battery power, being applied through circuit design. The present invention is applied for safety management of vehicle batteries with an engine starter and a charging device.
Power supply for vehicles makes much of accuracy and safety. One of the most important purposes of power supply system is to supply vehicles and users stable, adequate and convenient electricity. The power consumption of vehicles is getting complicated because after the vehicle stops running, the batteries still supply power to electric appliances such as notebooks, book lights, audio devices, air conditioners, microwaves, and refrigerators, etc. Or the user may forget turn off head lamps so that the power exhaust after a period of time. The electric starting device of the vehicle such as starts requires certain voltage and current for starting the vehicle engine, thus further driving the generator. When the power exhausted or the voltage and current are lower than the requirements, the starting device of engine can't operate normally so that the vehicle engine can't be started. This leads to safety problem and inconvenience on usage.
In order to make vehicle have enough battery voltage and current to restart the starting device for driving the engine after stopping and turning off the engine, there are a lot of prior arts related to the battery power management. Refer to U.S. Pat. No. 6,437,575, the prior art measures and displays residual electricity of batteries. Or in Journal of Power Source, 2002, a study made by Mr. Johnson is to measure internal resistance of batteries. These prior arts provide prediction or warning effect.
After the engine stopping, power supply for battery charger also stops. The vehicle batteries are not charged. Along with the consumption of electricity, the batteries continue discharging, even exhaust, both the man battery as well as the backup battery. Refer to U.S. Pat. Nos. 4,493,001, 6,111,731 and 5,327,068, power supply from battery is cut off immediately or a period of time after the engines stopping running. However, there are more and more electric appliances being applied on vehicles and used after the engine stop such as notebooks, book lights, audio devices, air conditioners, microwaves, and refrigerators, etc. Other devices for general use included the security system or alarm lights on vehicle. Abnormal conditions for battery discharge such as forgetting to turn off head lamps, electric leakage to environment may also cause battery exhaustion. Therefore, it is important to ensure the battery with enough electricity for starting next time no matter for general use or under abnormal conditions.
Since after the engine stopping running, other peripherals electric appliances may be still in use. In order to prevent power exhaustion, the power should be managed. For sake of the safety, power supply from the main battery or the backup battery is cutoff depending on conditions. When the starting device restarts the engine, the disconnection may happen and cause break of the electric appliances or rebooting of the notebook. When the engine runs and the generator is driven to charge batteries, the electric appliances can be in use at the same time. Refer to U.S. Pat. No. 5,903,063, it applies the filtered and amplified ignition noise signal to a hysterics latch circuit. Without getting data from vehicle control computer, a battery protection device for an independent system is connected with a battery power source cable in parallel for detecting starting of vehicles. However, power consumption by both electric appliances and vehicle ignition discharges the batteries. Both generate voltage reduction or noise of battery power supply. From the noise or voltage reduction, only power consumption is learned. In order to check vehicle status such as stop or start, management status, safety and protection for battery power under conditions that various combinations of electric appliances are used when the engine is off or restarted, it is necessary to identify discharging pattern by the parallel power source cable. Then through the checking results, battery power source management for vehicles under normal or abnormal conditions is generated for safety of vehicles and drivers.